1. Field of the Invention
The present invention relates to an apparatus for detecting a phase difference, and more specifically, to an apparatus for detecting a phase difference using a charge pump module and a method thereof.
2. Description of the Prior Art
Many types of circuits, such as clock generators or RF transceivers, require a clock signal with highly precise phase. An imprecise phase of the clock signal will result in the mistake of the whole system. Generally speaking, the larger the phase error, the larger the jitter of output clock signal(s). Hence, for the systems which need precise clock signals, the larger phase error may result in a serious error in circuits of the next stages.
Phase differences in circuits can be adjusted when the phase differences can be detected. However, in some cases, the phase difference is so minute that the conventional phase detector cannot detect the phase difference between the two input signals.